<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <style>
      input[type='checkbox']#menu + div {
        display: none;
        border: solid 1px black;
        pad: 10px;
      }
      input[type='checkbox']#menu:checked + div {
        display: block;
      }
    </style>
    <label for="menu">Lee</label>
    <br />
    <input type="checkbox" name="menu" id="menu" hidden />
    <div class="menu">menu</div>
  </body>
</html>
